Displacement pumping system



Dec. 2, 1930. J. OLIPHANT 1,783,747

bIfLACEMENT PUMPING SYSTEM Filed April 18, 1927 2 Sheets-Sheet 2 diafne Patented Dec. 2, 1930 JOHN- QLIPHANT, or CHICAGO,'- ILLmoIs, nssreiron ro snnmvlmf-mnon mmw.icon-- v v rnuxncomomrron onmnssncnnsmwst s DISPLACEMENT summer? sirs'rEM M Y a neationiiiezraprilis; 1927:. seriali noi 184,785?

This inventionsrelates: displacement pumpingv systems and. more particularly to controlling. arrangements for such pumping 7 systems; 7

obj ect of the -.invention: is to provide] an improved displacement pumping, system.

Another object otthe inventionisto provide.

an :improved i displacement pumping .system' 7 havingimprovedscontrolling'cmechanism.. Y further. object of theinvention is to provide an improved controlling mechanism for dis-=- placement pumping systems in which liquid level Variation inthe displacement: tanksmay 'efiectcontrol of the pumping. fluid supplyand discharge relative tothe tanks through improved mechanism. A still furtherobject of the invention is to provideflan: improved controlling mechanism for a displacement pumping system in which the liquid level in. zmthe tanks may control through pilot. means the'shiftin'g of the main pumping, fluid controlling. valves. Other objects and advantagesof the invention will subsequently appean. 2512 In the accompanying, drawings I have shown for purposes of illustration: one form: which my invention may; assume in practice.

In these; 'drawings,l-

Fig; 1 is a: plan: view of a displacement; m pumping system in WhlOh'thB illustrative em-H bodiment of the'invention is incorporated-.1

Fig.2 is'a side elevation with parts broken away of the mechanism of Fig.1

' Fig, ,3 is an enlargedvertical section on 'the,

line 3+3 ofiFigrl. r

Fig. 4' is an enlarged vertical section: on the line Hot Fig.1.,

Referring tothe drawings, 1 represents a displacement pumpingunitcomprisinga plu 1 rality of alternately fillingzjand discharging tanks respectively designated2 andi3.- Each of "the tanks is provided with liquidsupply and discharge-means in the formpfa 'central-- connection 4 having branchesg5,and-.6which- 7 3. arev respectively controlled by [a discharge check-valve 7 and: an intake -check.valve 8.-{

This connectionis shown as being. at the hoti. tomof the tank although'itJw-ill be' understood that it'mayjbe made at anydesiredlaointfasfor example, at the top of the tank inawhich.v

' thecontrohof mechanism later to he -described: j from a receiiver 9 to which fluid "is supplied a by a compressor 10' through a'pipel1; and to facilitate filling of the tanks the fillingtanks are connectedwith x the intake side of the A- compressor: through a line-"12;"It will be understood that-a plurality of these-pumping units may' be used and operated byjthe same" compressor andwhere more thana single unit is employed the lines 11 and l2- may be ex tended as indicatediii-Fig.1. The admission of pumping;fiuid and the filling of the tanks 2 and -3 is contro'lled by a" commoniva'lve mechanism,-= generally "designated 15; which comprises; a casing 16- provided: with; a valve seat YT-upon "whieh 'aslide val-ve 18 is -re ciprocable; The' seat17'is traversedby ports 7 19; 20; 21 and '22 and the-slide valve; controls communication between the port 19 i and the ports -20a1id 22 by means-or its'outside edges a 23' 24' respectively; while" communication between the p'orts; 2O and 22 and the port 21 l 75.

pipe 27. if The-port'20communicates'with the tank-3 through connections later more fully describedg but including a pipe-28i The port I 21 communicates througlr a pipe 29with the V suction line-12; and' port' 22; thr0ugh con- 35 nection's inoludingafpi'pe 30,is communicable WiththetaIik QC-Y' V O'peratibn of "thevalve 18"iscontrolled by" 'meansfof a servo motor:32%comprising; a cyl-i ind'e'rj33 in which a pis'ton'fi l is reciprocable; go The piston 84 'lis'iconnectedaby .rod': 35

fiche: lvalt e LSEandstranSmits motion in oppo site: directions to the slatte'r 'on its ownioppo -i 7 site movements. The movements rot the pisgr ton, 3e 1" are controlled byf variations j in; the ;95. pressures at the opposite sidesfl-thereof land; thesuppliesrot fluid; to the-oppositeendsmt the. piston-3 L are respectively controlled mechanisms.- associatediwith the. tanks 2fandi.

3.. ,Herein the pressure conditions at the'e'nd 11 0 V of the cylinder 33 remote from the valve chest 16 are controlled by mechanism associated with the tank 2, while pressure conditions at the opposite side of the piston 34 are controlled by conditions in the tank 3. The cylinder 33 has a central exhaust port 36 which is uncovered as the piston 34 approaches the opposite ends of its path of movement and means for preventing excessive pressures at the ends of the cylinder as the piston approaches the latter are also provided, the same constituted herein by pinhole vents 36. Referring to Fig. 2, it will be observed that a suitable stop valve controlled line 371 com municates through a pressure reducing valve 38 with a branched connection 39 whose separate branches 40 and 41 lead respectively into juxtaposition to the tanks 2 and 3. Since the mechanism now to be described is substantially identical in the case of both tanks, that associated with the tank 3 will alone be described. 7 v 1 Referring particularly to Fig. 4, it will be noted that upon the top of tank 3 is mounted a casing 43 in free communication with the interior of the tank. A ball float 44 is guided for vertical movement in the chamber 43 by a stem 44 which at its lower end is movable in a bore 44 in a transverse bearing member 44 which prevents the float 44 from falling out of the chamber 43 into the tank. At the upper side of the ball 44, the stem is threaded into a suitably guided valve member 45, later more fully described, the latter being provided with a guided ope-rating stem 46, whereby the ball is adequately guided both at top and bottom. The valve 45 is provided with a seat-engaging, ring-like washer member 46 which is adapted to cooperate with a seat 47 surrounding a passage 48 connecting with the pipe 28. Accordingly on upward movement of the float 44, the packing 46 will engage the seat 4'7 and close communication between the chamber 43 and the pipe 28.

, ,This mechanism is a safety arrangement and has as its function precluding the possible entry of the liquid to be pumped, into the line 28. The passage 48 is formed in a cap member 49 which at its upper end supports a pilot valve housing 50. The latter contains a seat 51 for a ball valve 52 which is normally maintained seated by a spring 53, but which may be opened through engagement by the stem 46 on upward movement of the float 44. It

. will be noted that the stem 46 is of sufficient length to engage the valve 52 before the valve 45 engages its seat. The connection 41 com-:

municates with the space above thevalve 52 on the top of tank 3, while the connection 40 communicates with the similar connection at the top of tank 2. From below the seats of der 33 nearer the valve mechanism 15, while the valve 52 associated with the tank 2 controls supply to a connection 56 leading to the other end of cylinder 33.

It is believed that the mode of operation of the mechanism heretofore described will already be obvious, but a cycle of operations may be set forth. Let it be assumed that liquid under appropriate head or even from a level within the limits of lifting action of the suction of the compressor 10, has flowed into tank 2, filled the latter, and raised the float 44 in chamber43 on top of tank 2. Then valve 52 controlling connection 56 will be unseated by its rod 46 and pressure fluid will flow through line 37, reducing valve 38, line 40 and connection 56 to the right hand end of the cylinder 33 as viewed in Fig. The piston is shown, in the figure mentioned, moving from right to left, and obviously, with the tank 3 discharging, the gaseous pumping fluid therein would be transmitted through line 28, port 20, passage 26, port 22.andpassage 30 to fill the latter line and begin the discharging of liquid from tank 2. The piston 34, continuing its movement to the left, would finally open the exhaust port 36 and in that position would have moved valve 18 to uncover port 22 and connect ports 20 and 21. The left leak port 36 would permit ready movement of piston 34 as described. In left hand extreme position of piston 34 and valve 18, gaseous pumping fluid at full receiver pressure will flow through pipe 27, port 19, port 22, and pipe 30 to discharge the liquid from tank 2, and tank 3 will be connected through pipe 28, port 20, recess 25, port 21 and pipe 29 with the compressor intake so as to facilitate filling of tank 3. As soon as the liquid level in the chamber 43 at the top of tank 2 is lowered sufficiently to permit the float to drop and release the valve 52, no more air will be supplied through line 56 and the 1 pressure in the right hand end of cylinder would drop to atmospheric. The time required for shifting the valves is relatively short so that it will be moved to its extreme position before the liquid level in the chamber 43 is lowered sufficiently to cause the float 44 to drop enoughto permit closing of the valve 52. The valve 18 and piston 34', being substantially balanced, would remain in left hand position (Fig. 3), the friction on the packings offsetting the slight unbalanced pressure on valve 18. Now,1tw1ll be evident that when tank 3 is completely filled raising its float 44, the piston 34 and valve 18 will be moved to the right and the tank 3 emptied while tank 2 is filling.

From the foregoing description, it will be obvious that there'is provided an improved and advantageous displacement pumping mechanism in which means is provided whereby the liquid levels in the filling tanks control the admission of pumping fluid thereto while all risk of liquid entrance to the gaseous pumping fluid lines is prevented, in

which pumping fluid is conserved, in which each element of a unit-pair performs a con trolling function for the others as well as one for ltself, and 1n which a simple arrangement of parts and low operating pressures.

for the controlling devices are made possible.

While I have in this application speciflcal ly described one form which my invention may assume in practice, it willbe understood that this form of the same is shownfor'purposes of illustration and that the invention may be modified and embodied'in various other forms without departing from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is V V 1. In a displacement pump, a' displacement tank, pumping fluid supply -means therefor including means forminga connection opening through the top of the tank, controlling means for said pumping fluid supply means including a main" pressure fluid actuated valve, a pilot valve mounted on said tank in alinement with said connection for controlling flow of pressure fluid to actuate said main valve and a float in said tank for controlling said pllot valve, and means controlled by said float to prevent liquid entering said connection.

2. In a displacement pumping apparatus, a pair of displacement tanks, common valve mechanism for controlling supply of pumping fluid to and ventingvof pumping fluid from said tanks and for interconnecting the latter, and means associated with each of said tanksand controlled by'the level of" liquid therein for controlling moving of said valve mechanism in one direction.

3(In a displacement pumping apparatus, a pair of displacement tanks, common valve mechanism for controlling supply of pumping fluid to and venting of. pumping fluid from said. tanks, a piston for actuating said valve mechanism, a cylinder in which said piston lSleClPIOCdblG, and means for adm1tting fluid to one end of'said cylinder asso ciated with one of saidtanks and for admitting fluid to the other end of said cylinderassociated with the other of said tanks, said cylinder having a piston controlled exhaust midway between its ends, and other means for 1 further exhausting said cylinder.

4. In a displacement pumpmg apparatus, a

pair of displacement tanks, common valve mechanism for controlling supply of pumping fluid to and venting of pumping fluid from said tanks, a piston for actuating said valve mechanism, a cylinder in which said piston is reciprocable, and means for admitting fluid to one end of said cylinder associated with one of said tanks and for admitting fluid to the other end-of said cylinder associated with the other-of said tanks, said cylinderhavi ng a piston; controlled exhaust midway betweenf its ends and havingalsm means; for limiting r pressures built." up) 1 by. movement .fOf': said pistonz. into either end thereof. M V

1 25.111 a. displacement pumping apparatus, a pair of displacement tanks, common valve mechanism foeiconatuit supply of pumping fluid to and venting of pumping fluid from said tanks, a piston for actuating said valve mechanism, a-cylinder in which saidpistonis reciprocable, and means for admitting fluid. to one end of said. cylindertassociated with one of said tanks and for admitting fluid-to the other end of said cylinder associated with the other of said tanks, said cylinderhaving a piston controlled exhaust midway between its ends, said cylinder having vent ports of small area formed 1n each end thereof-for limiting pressures built up 'by movement of said piston.

6."In combination, a displacement tank having an open top, a float chamber mounted on saidtop and overlying and communicating.

with said opening, a float in said float chamher, a pumping fluid supply connection mountedin and opening into the top of said floatchamber, a valve seat surrounding the mouth of the supply connection, a valve mov able with said float and adapted toseaton said valve seat, a fluid pressure actuated valve for controlling supply and exhaust of fluid through said connection, and a pilot valve mechanism for controlling flow of pressure fluid to said first mentioned valve, said mechanism being supported on said fluidsupply connection and controlled by said float.

7. In a'displa'cement pumping apparatus, arpair of displacement tanks, valve mechanism for'controlling supply of pumping fluid to and venting of pumping fluid from said tanks, pressure'fluid actuated means for operating said valve mechanism, a pilot valve on one of'the tanks for controlling flow of fluid to said operating means to cause movement of'said valve mechanism to effect flow of pumping fluid for causing functioning of said tanks in one manner,'and a pilot valve on the other of said tanks for controlling flow ing into the tank, controllingmean's for said pumping fluid supply means including a main pressure fluid actuatedvalve, a pilot valve for'controlling flow of pressure fluid to actuate said main valve, and afloat in said tank for controlling said fiilot valve, and means controlled by said oat controlling communication between said connection and said tank to prevent liquid entering said connection.

In testimony whereof I affix my signature.

JOHN OLIPI-IANT. 

